2
Frontier Questions in Climate Change and Polar Ecosystems

The goal of the Polar Research Board’s workshop was to bring together a diverse group of scientists to identify key research frontiers at the intersection of polar ecosystems and global climate change. “Frontiers” in this context signifies those cutting edge ideas and research needs that will take the science forward into the coming decades. Workshop participants were asked to consider: Where does the science need to go next? What has been accomplished and what are the future questions to be answered? What are the next big innovative topics in this area of scientific research?

Through presentations and discussions, the workshop participants identified five key questions that represent forward-looking opportunities:

Will a rapidly shrinking cryosphere tip polar ecosystems into new states?

What are the key polar ecosystem processes that will be the “first responders” to climate forcing?

What are the bi-directional gateways and feedbacks between the poles and the global climate system?

How is climate change altering biodiversity in polar regions and what will be the regional and global impacts?

How will increases in human activities intensify ecosystem impacts in the polar regions?

The list is not intended to be unique or exhaustive and, indeed,

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2
Frontier Questions in
Climate Change and Polar Ecosystems
T
he goal of the Polar Research Board’s workshop was to bring
together a diverse group of scientists to identify key research fron-
tiers at the intersection of polar ecosystems and global climate
change. “Frontiers” in this context signifies those cutting edge ideas and
research needs that will take the science forward into the coming decades.
Workshop participants were asked to consider: Where does the science
need to go next? What has been accomplished and what are the future
questions to be answered? What are the next big innovative topics in this
area of scientific research?
Through presentations and discussions, the workshop participants
identified five key questions that represent forward-looking opportunities:
• ill a rapidly shrinking cryosphere tip polar ecosystems into new
W
states?
• hat are the key polar ecosystem processes that will be the “first
W
responders” to climate forcing?
• hat are the bi-directional gateways and feedbacks between the
W
poles and the global climate system?
• ow is climate change altering biodiversity in polar regions and
H
what will be the regional and global impacts?
• ow will increases in human activities intensify ecosystem impacts
H
in the polar regions?
The list is not intended to be unique or exhaustive and, indeed,
25

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26 FRONTIERS IN UNDERSTANDING CLIMATE CHANGE AND POLAR ECOSYSTEMS
relevant work is already occurring within the science community, as
described in the examples and case studies in Chapter 1.
WILL A RAPIDLy SHRINKINg CRyOSPHERE TIP
POLAR ECOSySTEMS INTO NEW STATES?
Many of the workshop participants emphasized the need to quantify
both the vulnerability and resilience of the polar ecosystems, including
local communities and populations, in response to the rapidly shrinking
cryosphere, and to understand the connectivity between the cryosphere
and the global system. Changes in air temperature and precipitation pat-
terns are altering the structure of the cryosphere, the hydrological cycle,
fire regimes, and permafrost melting in the terrestrial system. Warming
atmospheric and seawater temperatures over the western Arctic (Chukchi
Sea and Canada Basin) and the western Antarctic Peninsula have dramati-
cally reduced sea ice cover, changing air-sea interactions regionally and
their connectivity to the global system.
The polar regions are poised to lose biodiversity as the result of air,
sea, and land temperature changes and seasonal-to-total melting of sea
ice, glaciers, and permafrost. Changes in biodiversity can be expected to
result in altered biogeochemical processes, which can affect the overall
production of the system. For example, a shift in dominance from krill-
eating Adelie penguins to fish-eating seals can alter the net efficiency of
biogeochemical processing. If the dominant higher trophic animal is eat-
ing higher on the food chain (fish-eating seals) versus feeding lower on
the food chain (krill-eating penguins), the system is less efficient as more
total energy is used to get the same base level of food to the top predator,
requiring more food at the base of the food chain.
Other impacts of a shrinking cryosphere include changes to subsis-
tence life styles, resource exploration, and tourism. Coastal erosion is
increasing as sea ice retreats and open water can degrade coastal regions
and negatively impact human habitation. Increased potential for resource
access and extraction may be realized as the open water season increases
in length (Arctic Council, 2009). Traditional hunting methods and sites
are changing with changes in weather, the landscape, and resource avail-
ability (e.g., Ford et al., 2008). Understanding ecosystem changes with
climate forcing, their complexities, vulnerabilities, and feedbacks are con-
sidered important research frontiers in a world that continues to warm.
Workshop participants stressed the important goal of coupling climate
models with biogeochemical models in order to identify potential tip-
ping points and associated tipping elements, transformational processes,

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FRONTIER QUESTIONS IN CLIMATE CHANGE AND POLAR ECOSYSTEMS
and thresholds within polar regions to ultimately develop strategies to
minimize and/or adapt to the impact of climate change on ecosystem
services and processes.
A tipping point describes a critical threshold reached in a nonlinear
system, where a small perturbation to the system can cause a shift from
one stable state to another (see Box 1.1). The global climate system is a
nonlinear system and there are several possible tipping points that could
potentially be reached this century as a result of human-induced activi-
ties. These have been referred to as “policy-relevant” tipping points (Len-
ton et al., 2008; see Figure 2.1 for examples). Abrupt climate change can be
considered a sub-type of tipping point, where a climate system response
is faster than the cause itself (NRC, 2002). Lenton et al. (2008) describes
“tipping elements” as large-scale components of the Earth system (at
least subcontinental in scale) that may pass a tipping point. The transi-
tion of the tipping element in response to forcing can be faster, slower,
or no different in rate than the cause, and can be either reversible or
irreversible. Although variable in nature, the inherent common property
of these tipping elements is that they exhibit “threshold-type behavior in
response to anthropogenic climate forcing, where a small perturbation at
a critical point qualitatively alters the future fate of the system” (Lenton
et al., 2008). A large proportion of defined tipping elements have direct
relevance to polar regions, not only because these areas are warming more
rapidly than any other place on Earth, but also because these tipping
elements typically involve amplifying ice-albedo and greenhouse gas
feedbacks that are specific to high-latitude regions.
Declining seasonal sea ice and the disappearance of the Arctic peren-
nial sea ice pack, as well as the shrinking Greenland and West Antarctic
ice sheets are processes of particular concern to the workshop participants
because of their inevitability and/or severity of impacts and the potential
for tipping points to be reached. Additional processes with potential tip-
ping points of concern include dieback of the boreal forest, a northward
shifting treeline into tundra regions, CO2 and CH4 release from carbon-
rich permafrost soils, and release of marine methane hydrates from sub-
sea permafrost. Recent work has been put forth advancing the ability to
anticipate and forecast an approaching tipping point in the Earth’s climate
system, where an initial slowing down in response to a perturbation is
commonly experienced (e.g., Dakos et al., 2008). Advances in modeling
and forecasting an approaching tipping element may enable us to further
understand whether these critical thresholds and their repercussions can
be avoided (i.e., mitigation) and/or whether they can be tolerated (i.e.,
adaptation).

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28
FIguRE 2.1 Potential policy-relevant tipping elements in the climate system. Subsystems indicated could exhibit threshold-type
behavior in response to anthropogenic climate forcing, where a small perturbation at a critical point qualitatively alters the future
fate of the system. SOURCE: Lenton et al. (2008; Copyright 2008, National Academy of Sciences, U.S.A.).

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FRONTIER QUESTIONS IN CLIMATE CHANGE AND POLAR ECOSYSTEMS
WHAT ARE THE KEy POLAR ECOSySTEM PROCESSES THAT
WILL bE THE “FIRST RESPONDERS” TO CLIMATE FORCINg?
Workshop participants discussed the role of Arctic and Antarctic
polar regions in highly coupled systems, with strong links between land,
ocean, ice, atmosphere, and humans. These individual components can-
not be fully understood independently of one another, as a perturbation
to one system component will likely cause cascading effects throughout
the entire polar system. For example, current regional and global models
have not been able to accurately capture patterns of recent Arctic change
(e.g., sea ice decline) and pathways for model improvements are currently
sought. Some of the workshop participants emphasized the importance of
understanding and quantifying the system interactions (rather than simply
the isolated components) to accurately predict polar ecosystem response
to climate forcing. Models that address the complex interactions between
living organisms and their environment (i.e., a focus on “biocomplexity”)
are critical to understanding how climate change influences ecosystem
processes. Developing these models in concert with observational studies
is essential to developing predictive tools that are useful to policymakers
and have benefits for society. As such, these models can be used to sup-
port judgments to create adaptive systems of decision making.
Terrestrial
In the terrestrial realm, major uncertainties in current modeling capa-
bilities include the ability to quantify shifts and feedbacks associated with
ecosystem disturbances (e.g., fires, logging, insect infestation), migrations
of flora and fauna, coastal erosion, and hydrological and carbon-related
impacts of warming and permafrost degradation. Major ice-albedo and
greenhouse gas feedbacks may be associated with these changes as well.
These feedbacks have the potential to drastically alter predicted outcomes if
they are not modeled properly. For example, it is estimated that ~1024 Pg C
is currently locked away in the top 0–3 meters of permafrost soils (which
amounts to twice the current atmospheric carbon pool) (Schuur et al.,
2008). However, with warming and permafrost thaw, this pool of carbon
may be reintroduced to the contemporary carbon cycle through release
of significant CO2 and CH4 to the atmosphere through decomposition
and methanogenesis of organic carbon. Major uncertainties surrounding
the rates of change in these scenarios of permafrost thaw, the magnitude
of released CO2 and CH4 to the atmosphere, as well as whether climate
forcing will result in wetter or drier landscapes, need to be resolved if
the overall impact and the direction of feedbacks to the polar and global
climate system is to be assessed critically. Improved modeling capabilities
and understanding of system interactions are not only essential to improve

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30 FRONTIERS IN UNDERSTANDING CLIMATE CHANGE AND POLAR ECOSYSTEMS
the ability to predict polar ecosystems responses to climate, but, because
of globally significant feedbacks, are also essential to improve knowledge
of the overall polar and global climate system as well.
The ice-free continental ecosystems of the Antarctic are microbially
dominated and are driven to a large extent by the summer production of
liquid water and the distribution of biotic and abiotic matter by wind. To
accurately predict ecosystem responses to warming in both the Antarctic
and Arctic, models need to include coupled information on surface energy
balance, hydrology, and biological/biogeochemistry. Accurate models
should also emphasize connectivity among the components and utilize (i)
high resolution digital elevation data (e.g., from LIDAR) so that the spatial
reference of each modeled segment is properly connected to the others,
(ii) high resolution remote sensing (Quickbird and Worldview) data to
classify the status of every control volume, (iii) data from field observa-
tions/experiments to determine biogeochemical cycling rates and food
web/populations dynamics, (iv) stoichiometry of material and energy
transformation within each control volume, and (v) matter and energy
transfer at the surface via aeolian or water transport. High resolution
meteorological and stream hydrology records can provide direct input to
the latter components. These spatially explicit process-based models can
further include the presence of particular genes, microbes, or nutrients
at any point in the landscape, which will allow prediction of the role of
wind versus water in promoting growth and movement of biological
components of the ecosystem.
Marine
The strong dependence of Arctic and Antarctic polar marine organ-
isms on seasonal sea ice provides the principal connection between eco-
systems and climate in these regions. Better understanding of how polar
marine ecosystems respond to climate change requires improved models
of coupled atmosphere-ocean-ecosystem dynamics at local, regional, and
global scales, informed and driven by new observations. Better prediction
of polar ecosystem changes requires new models of coupled global-scale
atmosphere-ocean circulation that simulates the teleconnections between
lower-latitude climate variability and high latitude responses of atmo-
spheric pressure and wind fields, ocean circulation, and sea ice. A good
example is the sea ice of the southwest Pacific Ocean/Bellingshausen Sea
sector of the Southern Ocean, which exhibits strong covariability with the
El Niño-Southern Oscillation (ENSO). Annual advance and retreat of sea
ice and the resulting duration and extent are strongly modulated by the
interactions of ENSO with the Annular Modes that modify wind speed
and direction in spring and fall. Forcing of the Southern Annular Mode

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FRONTIER QUESTIONS IN CLIMATE CHANGE AND POLAR ECOSYSTEMS
by the combined and interacting anthropogenic effects of the ozone hole
and greenhouse warming also indicate how better understanding and
improved predictive capabilities rest on comprehensive coupled model-
ing tools.
In general, current models do a poor job simulating high latitude
sea ice variability and these shortcomings hamper realistic simulations
of atmospheric and oceanic circulation. In addition, deep water forma-
tion will be strongly affected by accurate representations of areas of new
sea ice formation, which in turn are affected by ice shelf-ocean and con-
tinental shelf-ocean interactions, all of which are poorly resolved (or
coarsely parameterized). Circumpolar sea ice extent can be reasonably
reproduced, but resolving regional and seasonal sea ice variability is
still a challenge. Sea ice and snow thickness, rafting/ridging, snow-ice
flooding, and melt-ponding are all a challenge even for higher-resolution
regional sea ice models, largely because of the lack of data, both for evalu-
ation purposes and for forcing the sea ice models (e.g., accurate regional
resolution of winds and upper ocean data). Accurately simulating open
water areas (leads, polynyas) is another challenge, which will ultimately
affect the prediction of ocean-atmosphere heat fluxes and the consequent
strong positive feedbacks. Lack of skill in representation of sea ice dynam-
ics also affects modeling of ocean vertical mixing processes that are critical
to plankton dynamics. New observations of these sea ice properties and
ocean dynamics at all scales are critical to improved model development
and understanding.
Marine ecosystem models have reasonable utility in representing bulk
phytoplankton distributions (chlorophyll), for which remotely-sensed
data are available, and for which we have reasonably good understanding
of the fundamental biophysics underlying the ecology. Even so, detailed
modeling of community dynamics like the observed transition from
diatom-dominated to cryptophyte-dominated communities along the
Western Antarctic Peninsula is still a frontier area. Modeling the potential
impacts of lower trophic level species changes on marine carbon cycling,
such as the impact of a shift to smaller phytoplankton species produc-
tion observed in the Western Amerasian Arctic with increased freshwater
content (Li et al., 2009), is critical to forecasting potential large-scale eco-
system response to climate forcing. Until the details of lower trophic level
community response to climate change are better understood, mecha-
nistic modeling of the upper trophic levels cannot progress. Further up
the foodchain, the behavior of individual predators becomes paramount
and modeling of functional groups as chemical reactors (as with bulk
chlorophyll) is inadequate, instead requiring more detailed information
on lower trophic species composition. The divergence of characteristic
time and space scales between the base and apex of foodwebs from days

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32 FRONTIERS IN UNDERSTANDING CLIMATE CHANGE AND POLAR ECOSYSTEMS
and meters to decades and ocean basins also remains a large challenge
facing climate-ecosystem models.
WHAT ARE THE bI-DIRECTIONAL gATEWAyS AND FEEDbACKS
bETWEEN THE POLES AND THE gLObAL CLIMATE SySTEM?
Workshop participants emphasized that polar regions and lower lati-
tude ecosystems are parts of a coupled Earth system. For many ecosys-
tem processes, changes in one component elicit responses from other
components, which can further alter other system components. This cas-
cade of bi-directional connectivity makes atmosphere-ecosystem interac-
tions among the most complex in the natural world (NRC, 2007). These
responses and interactions become even more complex with the involve-
ment of human actions as broad ecosystem drivers. Given the complexity
of these interactions and the feedbacks involved, participants stressed that
breakthroughs will require effective collaboration among a wide range of
sciences and long-term ecosystem monitoring, as well as involvement
of multiple funding agencies.
Studies to date have shown unequivocally that climate change has
produced many direct regional impacts at the poles (IPCC, 2007b). Polar
regions are expected to be primary drivers of the global climate system
because of the strong modification of the surface-energy budget through
snow and ice cover, which is tightly coupled to the global circulation of
the atmosphere and the ocean. The global implications and associated
feedbacks of these polar impacts are difficult to define, and require long-
term on-site monitoring and experimentation, in concert with coupled
modeling efforts, to resolve. Participants noted that such efforts should
focus on the construction of scenarios that cross many scales, a dynamic
that we currently have little quantitative knowledge of.
Workshop participants discussed a number of processes and phenom-
ena (including those identified in Anisimov et al. [2007]) that may have
bi-directional feedbacks on the global system:
• Atmospheric variation: Changes in the polar energy sink region
exert a strong influence on the mid- and high-latitude climate by
modulating the strength of the sub-polar westerlies and storm
tracks (Dethloff et al., 2009). Disturbances in the wintertime Arctic
sea-ice and snow cover may induce perturbations in the zonal and
meridional planetary wave-train from the tropics over the mid-
latitudes into the Arctic. Consequently, Arctic processes can feed
back on the global climate system via an atmospheric wave bridge
between the energy source in the tropics and the energy sink in the
polar regions.

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FRONTIER QUESTIONS IN CLIMATE CHANGE AND POLAR ECOSYSTEMS
• Sea level rise: Of the many potential processes that influence sea
level, melting of polar glaciers and ice sheets is perhaps the most
tightly linked to atmosphere. Melting and direct ice discharge of
the Greenland and Antarctic ice sheets would produce about 7 and
61 meters of sea-level rise, respectively (IPCC, 2001). The collapse
of the grounded interior reservoir of the West Antarctic Ice Sheet
would also contribute significantly to sea level. Rising sea levels
would cascade through the world’s tightly connected economic
and political systems producing catastrophic global impacts.
• Ocean circulation: The increase in freshwater input to the sea
could influence ocean circulation producing wide spread global
impacts (Lemke et al., 2007). Models have indicated that arctic polar
warming and moistening are important on a global scale because
associated enhancement of sea-ice melting and freshwater inflow
to the Arctic Ocean plays a critical role in controlling the deep
convection and ocean meridional circulation, which in turn affects
global climate (Kug et al., 2010). In addition to tidal processes and
melting of Antarctic glacial ice, changes in atmospheric circula-
tion patterns have also been attributed to the increased upwelling
of Circumpolar Deep Water on continental shelves bordering the
West Antarctic Ice Sheet (WAIS) (e.g., Thoma et al., 2008). In turn,
these atmosphere-ocean and related sea changes have been impli-
cated in amplifying the warming trend over the WAIS (Steig et al.,
2009). Unfortunately, details of the actual mechanisms are lacking,
emphasizing the need to better resolve ocean processes in particu-
lar, and pointing to a need for increased ocean observations.
• Albedo: Surface albedo has long been recognized as one of the
key surface parameters in climate models through its direct effect
on the energy balance (Dethloff et al., 2006). Observed changes in
snow, ice, and vegetation cover are all producing changes in sur-
face albedo. Holland and Bitz (2003) have suggested that the rapid
loss of snow and sea-ice in certain areas of the Arctic can produce
feedbacks that can affect climate change over larger scales.
• Arctic terrestrial carbon flux: Some models indicate that, in the next
century, terrestrial ecosystems will act as a carbon sink (Stephens et
al., 2007; Baker, 2007). However, there are large uncertainties due to
the complexity of the processes and it is also possible that melting
permafrost and the associated increased carbon emissions will lead
to positive climate forcing (Sitch et al., 2007).
• biome shifts and migration patterns: Species that migrate between
low and high latitudes may be significantly influenced by chang-
ing polar ecosystem dynamics (Alerstam et al., 2007; Wilcove and
Wikelski, 2008). The rapid climate warming occurring in Alaska

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34 FRONTIERS IN UNDERSTANDING CLIMATE CHANGE AND POLAR ECOSYSTEMS
has led to drastic changes in forest ecosystems. Such changes can
lead to potential shifts in bird and large mammal migration pat-
terns. Likewise, changes in ocean pH, temperature, and circulation
patterns can reach thresholds that will eventually alter plankton
distribution and the migration patterns of marine fish and mammal
populations. Once these thresholds are reached, biodiversity at the
species and genetic levels will almost certainly be altered.
• Methane hydrates: Methane hydrates are known to be abundant in
marine sediments, particularly those associated with the continen-
tal shelves of the Arctic (Kvenvolden, 1988). As ocean temperatures
warm, either directly or as the consequence of altered circulation
patterns, the hydrates can become unstable and release significant
amounts of methane, a potent green house gas, to the atmosphere
(Sloan, 2003; Maslin, 2004). This marine efflux of methane can exac-
erbate warming at the global scale. For example, Shakhova et al.
(2010) have recently suggested that atmospheric release of a small
amount of methane from the East Siberian Arctic Shelf could lead
to abrupt warming.
• Southern Ocean biological production: Regional and global
models indicate that heat transport and associated stratification
of the Southern Ocean will change in response to climate forcing
(Ganachaud and Wunsch, 2000; Boning et al., 2008). In concert
with the prediction of amplified ocean acidification in south polar
waters, it can be expected that these changes in the physical envi-
ronment will influence the species composition and rate of primary
production in the Southern Ocean. Such changes may alter the
production of methane sulfonic acid, a potent cloud nucleator,
to the atmosphere, and change the sequestration of atmospheric
carbon dioxide and transport to the deep ocean. Such physical and
biochemical processes influencing changes in biological production
are also being studied regionally in the Arctic Ocean.
HOW IS CLIMATE CHANgE ALTERINg bIODIVERSITy
IN POLAR REgIONS AND WHAT WILL bE THE
REgIONAL AND gLObAL IMPACTS?
Terrestrial
The rapid warming of the Arctic is potentially leading to rapid shifts
in productivity, habitat, and biodiversity that are likely to have profound
implications for northern ecosystems and for the globe. Macroecology, the
subfield that deals with the study of relationships between organisms and

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FRONTIER QUESTIONS IN CLIMATE CHANGE AND POLAR ECOSYSTEMS
their environments at large spatial scales to characterize and explain pat-
terns of abundance, distribution, and diversity (Brown and Maurer, 1989),
will likely bring an important perspective to understanding regional and
global impacts. Understanding pattern and process in macroecology pres-
ents a considerable methodological challenge, as the scales of interest are
simply too large for the traditional ecological approach of experimen-
tal manipulation to be possible or ethical (Blackburn and Gaston, 2003;
Blackburn, 2004).
Alaska populations of boreal plants and animals contain mixtures of
Eurasian species and genes, making Alaska a center of boreal biodiversity
from the global perspective. The boreal forest is distinctive in being domi-
nated by conifers from the large landscape perspective. Most of the boreal
conifer tree species can attain long life spans, and if they survive to old
age, they become a specialized habitat for a set of highly adapted plant
(e.g., arboreal lichens, mosses) and animal (e.g., woodpeckers, cavity-
nesting bird) species. Human inhabitants are also dependent on a number
of critical forest resources in the Arctic (e.g., Usher et al., 2005 and refer-
ences therein).
Boreal conifers play a key role in enabling fire to propagate across
landscapes. In the past, warm temperature anomalies that trigger or pro-
mote boreal forest disturbance events, such as fire and tree-killing insect
outbreaks, were infrequent. However, in the warmer climate of recent
decades disturbances triggered by warm temperatures have occurred so
frequently and severely that a substantial reduction in older forest has
occurred already (ACIA, 2005). An inescapable consequence of the recent
rapid warming and other anthropogenic changes (e.g., increased trade
and travel) in the far north is the introduction of an increasing number of
species from the south (or from the southeast in the case of Alaska), where
species richness is greater (ACIA, 2004). In addition, a principal risk for
boreal forest is that climate change appears to be happening so rapidly
that a continued shift in the location of areas with a climate optimum for
forest growth could outpace tree migration rates (Davis and Shaw, 2001).
If so, tree dispersal rates and habitat availability as controls over forest
migration will not have sufficient time to operate for the successful move-
ment of all gene types and species. Consequently, these forests may be
among the Earth’s most susceptible ecosystems with respect to the loss of
genetic and species diversity due to climatic change. Thus, a challenge for
science and resource management is to identify the diversity of adaptive
genetic types present in key boreal species. If genetic biodiversity dimin-
ishes, future human uses and opportunities in the boreal forest are likely
to be reduced, and ecosystem services, including sequestration of carbon,
are likely to be less effective.

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36 FRONTIERS IN UNDERSTANDING CLIMATE CHANGE AND POLAR ECOSYSTEMS
Marine
As in the terrestrial case, there is an increase in subarctic species
moving northward into the Arctic, with the potential for increased spe-
cies competition and major ecosystem reorganization. The biodiversity
of polar oceans is structured to a large extent by cold temperatures. The
Antarctic Ocean has had low, stable temperatures for at least 8 million
years, whereas the Arctic Ocean has been cold for only the last ~2.5 mil-
lion years. In response, organisms in Antarctic waters appear to have lost
much of their physiological ability to adjust to increased temperatures
(Peck, 2005) compared to Arctic species. For example, the Antarctic noto-
thenoid fishes, which are the most stenothermal animals known, die of
heat death at temperatures above 4 oC (Somero and DeVries, 1967). Con-
sequently, some workshop participants theorized that Antarctic marine
species might be more susceptible to the effects of regional and global
climate change than Arctic species.
In light of the regional warming trends observed in the polar marine
environment, it is important to consider marine biodiversity in the con-
text of long-term evolutionary processes in which the genetics of the
organisms is modified in ways that allow them to adapt to the tempera-
ture environment and short-term pulsed events. Genomic approaches to
identify the types of genetic mechanisms that provide organisms with the
abilities to adapt to environmental change and, conversely, to understand
what types of genetic limitations exist in stenotolerant organisms that
possess very limited abilities to tolerate and acclimate to temperature
changes, are needed to fully understand the effects that climate change
will have on polar marine biodiversity.
HOW WILL INCREASES IN HuMAN ACTIVITIES INTENSIFy
ECOSySTEM IMPACTS IN THE POLAR REgIONS?
Workshop participants commented on the possibility of increased
human activity in the polar regions as a result of greater access and more
open water days. Until the recent economic downturn, ecotourism was
increasing significantly. Shipping across northern routes has started and
is expected to increase as the number of ice-free days increases. Potential
impacts from such activities include disturbance to wildlife and cultural
resources from tourists, oil spills, discharge of gray and black water (sew-
age) from cruise ships, as well as the potential for invasive species and
diseases into these remote and previously difficult to access regions. Nat-
ural resource development in the Arctic is likely to be one of the key driv-
ers of marine activity in the future (Arctic Council, 2009). Approximately
13 percent of the world’s undiscovered oil may be found in the Arctic
(Gautier et al., 2009) and oil and fuel spills are among the most significant

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FRONTIER QUESTIONS IN CLIMATE CHANGE AND POLAR ECOSYSTEMS
threats in both polar regions. As increased open water allows additional
time for transit, the chances of oil and fuel spills increases. Additional risk
comes from the unpredictable nature of storms and ice, some of which are
large enough to sink or damage ships.
In the Arctic, tourism has occurred since the early 1800s. The earliest
Arctic tourists were individuals attracted to abundant fisheries, exotic
wildlife species, and remote regions. Today, with improved access and
technology allowing more comfortable travel and easier access, these
numbers have rapidly increased. In fact, tourism has become the largest
human presence in many regions of the Arctic (UNEP, 2007). There are
serious concerns that tourism is promoting environmental degradation
in the polar regions in both the Arctic and Antarctic by putting extra
pressures on land, wildlife, water, transportation, and other basic neces-
sities. There are also cultural and social impacts to consider in the Arctic.
Examples include inappropriate visitor behavior that violates traditional
customs and disturbance of cultural sites or removal of cultural objects.
Conversely, there may be positive local economic impacts from the tourist
industry (e.g., job creation and the use of local transport, accommoda-
tions, and eating establishments).
In the Antarctic, tourism has grown rapidly in recent years with
approximately 45,000 visitors to the region during the 2007-2008 sea-
son (IAATO, 2008), up from less than 10,000 per year during the 1990s
(IAATO, 1997). Large cruise ship tourism, as well as small boat cruising
and landings make up the majority of activities with impacts on the polar
regions. These visits occur at the most sensitive time for the region, the
polar summer, when resident species are present and tending young,
feeding, and fledging. There has also been a recent upswing in the use of
Antarctica and the Arctic as sites for “extreme adventure” trips and “cli-
mate tourism” (tourists who wish to see a region and its species before
potential extinction caused by climate change) often requiring detailed
planning and logistical support. Smaller expeditions may not plan ade-
quately and may resort to “humanitarian” requests for aid from shipping
or nearby national bases when they encounter problems. There are also
impacts incurred by scientific researchers, however, these impacts tend to
be more constrained to the areas surrounding the research stations.